add period

Author: ShiCheng-Lu

docs/campaigns.mdx

@@ -63,7 +63,7 @@ Under advanced options, you can find User ID (the [external ID](/sdk/ios#identif
 
 You can configure the notifications Radar sends to users when they enter a geofence or place. Customize the notification body, and optionally, the notification title and the deep link URL.
 
-You can add metadata to the campaign, which will be accessible when the notification is triggered. In iOS the metadata can be accessed from `userNotificationCenter(_:didReceive response:)` with `response.notification.request.content.userInfo["campaignMetadata"]`
+You can add metadata to the campaign, which will be accessible when the notification is triggered. In iOS the metadata can be accessed from `userNotificationCenter(_:didReceive response:)` with `response.notification.request.content.userInfo["campaignMetadata"]`.
 
 ## Frequency capping